Your going to have it made or have it made. You don't need a sagia bolt. The 458 is not high pressure its a pistol round. 308 saiga bolt won't fit a normal trunion its to wide. I can make you a barrel if you supply a reamer an a blank.

BTW TONY AT TROMIX BUILT A FEW AKS IN 458 SOCOM HE WAS ALSO ONE OF THE ORIGINATORS OF THE ROUND. HE MIGHT BE ABLE TO HELP YOU. HE POSTS HERE ONCE IN A WHILE. PER A EMIAL HE SENT ME YEARS AGO ABOUT THE 458 AN WHAT COMPONETS HE USED THE BOLT WAS A STANDARD BOLT .

A STANDARD BOLT HEAD CAN BE OPENED UP TO .470 PRETTY EASY OR A GALIL 308 BOLT HEAD CAN BE USED. IF YOU HAVE A SOURCE FOR A 308 SAIGA BOLT PLEASE PM ME I SORT OF NEED ONE KIND OF BAD. I HAVENT SEEN ONE FOR SALE IN OVER THREE YEARS AN THAT WAS WITH A DEMILLED 308 SAIGA ON GUN BROKER THAT WENT FOR WAY TO MUCH. THAT THIRD LUG RIDES OVER THE AMMO IN THE MAG AN CAN CAUSE ISSUES IF YOU DONT NEED IT BEST TO AVOID IT.

DO A SEARCH HERE IN THIS AREA THERE IS A FEW THREADS ON THE 458. THE 450 BUSH MASTER MIGHT BE A BETTER ROUND FOR WHAT YOU HAVE IN MIND ALSO IF THERE IS BRASS OUT THERE.

PM ME IF YOU NEED ANY THING MADE BARREL WISE I MIGHT BE UP TO SPLITTING THE COST OF A REAMER AS ID LIKE ONE MY SELF .

As i recall its classifed as a pistol round I could be wrong . maybe im thinking of the 50 beowulf its been awhile since i looked hard at this stuff . I do recal one of them being technicaly a pistol round an that the pressures were pretty low. either way the pressures for the 458 SOCOM were kept at a safe in a ar15 level as thats what the round was designed for. IMO it would be safe in a ak on a standard bolt.

If it is or is not dont really matter as there are certainly high pressure pistol rounds take the 460 S&W for example its way up there. BUT I VERY WELL MAY BE WRONG ON THIS AFTER THINKING ABOUT IT.

OPINIONS ARE LIKE ASS HOLES DONT TAKE MINE AS PROOF ANYTHING IS OK I GOT A D+ IN MATH LOL

WELL FROM THE SOCOM SITE IT SAYS IT USES PISTOL PRIMERS AN THE BRASS IS MADE BY STARLINE THAT WAY. SO I GUESS TECHNICALY ITS A PISTOL CASE????????

THE BELWOULF HAS A 33,000 PSI LIMIT BTW FROM WHAT THE INTERWEB TELLS ME.

Development History of the .458 SOCOM Cartridge

The .458 SOCOM cartridge was developed around 2000 as a result of an informal discussion with a senior member of the US Special Operations community following the Operation "Gothic Serpent" debacle in Mogadishu, Somalia, as described in the book “Blackhawk Down”. In the book (and in private discussions), members of TF Ranger and USSFOD-D comment on the apparent ineffectiveness of the 5.56mm ammunition in their engagement of the assailants, stating that often multiple shots were required to disable a target. These concerns and those of others were formalized in a briefing to the commander of Naval Special Warfare and later studies have showed that indeed, from the shorter barreled .223-caliber weapons (e.g. M4 and Mk18), the angle of attack of the bullet could affect the performance dramatically.

The aforementioned discussion (which took place over beer and grilled top sirloin) focused on the possibility of developing a new cartridge capable of providing superior stopping power for AR-15/M-16 based weapon systems. An obvious first candidate was the 7.62 x 39 M43 cartridge that originated in the former Soviet Bloc. As the AR-15/M-16 had already been adapted to fire this cartridge, this seemed a simple solution. To increase the flexibility of the new cartridge, however, the decision was made to increase the bullet diameter to be able to employ heavier projectiles. This, too, has already been explored by the Soviets in the 9mm "Grom" and 9 x 39mm variant of the M43 cartridge. Due to restrictions in importing 9 x 39 ammunition, an alternate solution was required.

The idea of modifying the 6mm PPC case to accept the 9mm bullet was explored, but dismissed as it seemed to offer too much potential for disaster by accidentally chambering either a standard 7.62 x 39 round or 6mm PPC round in a rifle chambered in “9mm PPC”. To avoid this issue, a new and separate cartridge was developed from .30 Remington brass, dubbed the .358 CQB, to offer similar performance as the 9 x 39. This cartridge was designed to accept the standard .357 caliber JHP bullets, as well as the heavy (200-250 gr.) .358 caliber hunting bullets, the latter for subsonic suppressed applications. By choosing the 35 caliber, existing 9mm suppressors could be used without modification, and standard 7.62x39 magazines would accept the cartridge.

The .358 CQB was abandoned after .30 Remington brass supplies dried up (we now suspect that the 6.8 SPC design team was buying up all said brass for their development work) and the cartridge design did not meet the desired criteria of having a shoulder for headspacing.

Around this time, attention was drawn to the .45 Professional as designed by Tim LeGendre for the AR-15. This round seemed to offer even greater potential for delivering energy on target, but seemed to be plagued by one major drawback: the developer of the round had gone on record in an article published around that time that bolts of GM proprietary metallurgy were required, thus making retrofit of existing rifles difficult. In addition, this round uses the .451 caliber pistol bullets, limiting the bullet choice to projectiles of no more than 300 gr. (at that time, no heavier .451 - .452 bullets were available commercially). Later this round would be the inspiration for the .450 Bushmaster cartridge (a slightly modified version of the .45 Professional).

To offer the greatest flexibility to the user, the decision was made to design the new cartridge in .458 caliber. This offered the user a vast choice of commercially available bullets, ranging from 300 gr. HP and Spitzers, 405 gr. FN, up to 500 gr. Solids and Tungsten Core RN. The use of the Hornady 45 caliber sabot with the 38 caliber 158 gr. JHP used for muzzleloading rifles seemed to be feasible as well (later experiments appear inconclusive, partly due to the fact that the sabot is actually .451 caliber and not .458). This decision was strengthened after a literature search revealed two similar designs, the .458 Whisper and the .458 x 1.5”. Both had been designed to fire the heavy (500 – 600 gr.) bullets at subsonic velocities, and the Barnes .458 x 1.5” briefly saw service in Vietnam in the Special Operations community.

With the caliber decision out of the way, the case had to be designed. It is then that we happened upon the Tromix Sledgehammers in .50 AE and .440 Corbon. These rounds were capable of using bolts of standard metallurgy, thus resolving the issue of bolt retrofit. Problem, however, was the fact that the magazines had to be altered to accept the “short” pistol cartridge. A case of the same diameter as the .50AE that would fill the AR-15 magazine completely seemed the choice.

First designs used the 8 x 68 S case, as it shares the rim diameter of the .50AE and is non-rebated. Discussions with Tony Rumore revealed, however, that the .50AE and its wide rim posed an issue in that quite a bit of material had to be removed from the bolt lugs to make it work. He recommended against this design, and we went back to the drawing board.
The use of an even more drastically rebated rim seemed the solution, and the 0.473” diameter rim employed by the .308 and .30-06 based cartridges was chosen, as this would allow easy retrofit of bolt action rifles in this caliber. A review of existing cartridges showed that the .423 Westley Richards cartridge was the ideal solution, as it had all the proper measurements. Except one: Price. At about $4 per cartridge, this design was not going to be economically viable.

As fate would have it, around that time another new cartridge was being introduced at the 1999 SHOT Show in Atlanta by a small company called Anglo-American. This was a US "branch" of (former) Parker-Hale employees and they were showing two prototype uppers in a prototype .499 caliber cartridge. In reality, however, these uppers did NOT have chambers and the barrels were actually .458 caliber, as the cartridge design had not been finalized. The initial design called for a .499 diameter bullet and a 40mm long case (!). By 2000 the company had changed names to Leitner-Wise and was advertising their .499 LW and they were contacted regarding this cartridge and the availability of brass. The folks at L-W revealed that Starline would be supplying the brass for their cartridge, so...

Starline Brass was contacted and asked for what was thought to be the impossible: A pre-production run of .50AE brass, but unformed, untrimmed AND with the rim rebated to 0.473”. The .499 L-W project was mentioned to see if it would be possible to "tack on" to their order, but Starline replied that the L-W team had yet to decide on case dimensions and that no order had been put into the system because of that. However, they agreed to make the SOCOM prototpye cases, and shortly thereafter shipped the initial 2000 cases. Not until AFTER those cases were received did L-W actually send an Email with the "final" dimensions for the .499 L-W but soon thereafter, the two main proprietors of L-W had a "falling out" and purportedly went their separate ways.

Dave Davison at CH Tool and Die was contacted and he developed the initial dies. After one change, shortening the neck from 0.45” to 0.35” (for purely aesthetic reasons, well, that and it increases the case capacity…) the final design as it is now known resulted. Drawings were sent to obtain a custom reamer, and once all the parts – cases, dies and reamer – were available, these were sent to Tony at Tromix, along with some initial loads developed on QuickLoad.

Initial loads, and the overall case, were designed around the Barnes 300 gr. X Spitzer, as this appeared to be the lightest spitzer bullet available, which was thought to offer the best ballistic coefficient. The Lost River 400 gr. J36 offered a better BC, but was far too long to leave enough powder capacity and still function through the AR magazine. Based on Tony’s initial response (“HOLY SHIT”), it appeared the SOCOM would do what we wanted it to do – hurl big chunks of metal at substantial velocity from unaltered AR-15 lowers and magazines – in full auto if so desired.

Thus the .458 SOCOM was born, with a 40 mm long case to allow the use of the Barnes 300 gr. X Spitzer and still function through the AR magazine, a rim rebated to 0.473” to allow easy retrofit to existing bolt actions AND leave more material on the AR bolt, and in .458 caliber to allow a wide range of bullet weights to be used. On top of that, by the fact that the case is a pistol case, it operates at relatively low pressure, and thus imparts less stress on parts of the rifle.

The name of the cartridge was chosen based on the caliber (obviously) and based on the fact that the initial impetus came from those “Beer and BBQ” discussions with our friends in special operations. In addition, the fact that the round was also inspired by the Barnes .458 x 1.5” which had seen action in Vietnam in a Special Operations role played a part in naming the cartridge.

.458 SOCOM FAQ

Who developed the .458 SOCOM? Was it Tromix?
The .458 SOCOM was developed by Marty ter Weeme, founder of Teppo Jutsu LLC around 2000. The impetus was an informal (“beer and barbeque”) discussion with a senior member of the US special operations community regarding the apparent lack of effectiveness of the 5.56 x 45 cartridge in recent conflict. In particular, the reports from members of Task Force Ranger in Mogadishu, Somalia (Operation Gothic Serpent) that multiple shots were required to neutralize members of the opposing force led to the request to develop a new cartridge that would deliver far more energy from short barrels at relatively short distances. After the design was completed, Tony Rumore of Tromix Corp in Broken Arrow, OK was contacted to build the first prototype. Based on the favorable reviews, commercial production was started and the initial rifles were produced by Tromix. Currently, several firms offer rifles or upper assemblies in this caliber, including AR-15s, AK-47s, single shot and bolt action rifles.

Can I form my own cases? Isn’t it just a necked .50AE?
You could form your own brass; however it would be economically unwise. The only case that has the proper base diameter and rim diameter is the .425 Wesley Richards, which runs about $4 a piece. Any other brass will not have the proper rim size, either too large or too small. In a pinch, you could form .458 SOCOM from .50 BeowulfTM but the rim would be smaller. The initial prototype brass bore the .50AE head stamp and this has caused some confusion. The SOCOM case is 1.575” long, the .50AE is 1.290” so therefore, you CANNOT form the SOCOM case from the AE case.

What does SOCOM stand for?
SOCOM refers to Special Operations COMmand, the joint service command based at McDill AFB, near Tampa, FL that governs the various special operations units such as Naval Special Warfare (“SEALs”), Army Special Forces (“Green Berets”) and Air Force Special Operations. The cartridge was given this name based on the original impetus from special operations mentioned above as well as the fact that a similar cartridge saw limited use in Vietnam with special operations as well.

You mentioned the .50 BeowulfTM. Which is better, the .458 SOCOM or the .50 BeowulfTM?
This is one of those debates that neither side wins. Both cartridges are very similar, yet they are quite different. We had access to some of the information on the predecessor of the .50 BeowulfTM when we designed the .458 SOCOM. We designed it the way we did for very specific reasons. I admit I cannot be impartial, but I will give as honest a comparison of the two as I can:
Rim size – the SOCOM rim is the same as the .308 Winchester (7.62 x 51), the Beowulf rim is the same as the 7.62 x 39 M43 cartridge used in the AK-47. The Beowulf rim is easier in that you can use existing bolts for the AR. The SOCOM rim is easier in that there are hundreds of thousands of (old) bolt action rifles that use this same rim and that could be retrofitted to the SOCOM (all the old Mausers ….)
Case length – the Beowulf is 4mm longer than the SOCOM. A lot of this extra room is taken up by the body of the bullet anyway, so it does not gain you that much.
Headspace – the Beowulf uses the case mouth, the SOCOM the shoulder. There are those that feel using the shoulder offers inherent greater accuracy potential, but both rounds are capable of just about the same accuracy. Both are intended to be used at the same maximum range as well, so it really does not matter much.
Bullet selection – this is where the SOCOM used to have the Beowulf beat, hands down, due to large variety of .458 bullets compared to the .500. But with the advent of the .500 S&W, the Beowulf is starting to catch up. As of 2010, bullet selection for both calibers has improved quite a bit, with all sorts of great new projectiles.
Cost/Selection – Before Rock River got into the game, the SOCOM uppers were all custom jobs whereas the Beowulf uppers were more “semi-bulk”. The SOCOM uppers are available in just about any configuration you can imagine, but that comes with a price tag. The Beowulf uppers come in a certain number of configurations but with a lower cost and they might be a little easier to get (again, before Rock River took up the .458 that is)
Power – Let’s be honest. The difference between a .458” bullet and a .500” bullet is a whopping 0.042” or a hair under 3/64”. If you hit anything with either, it will be hurting or dead. That 0.042” won’t matter a bit. Both have just about the same muzzle velocity so just about the same power. The Beowulf has a little more room for powder and with the slightly larger diameter bullet will edge out the SOCOM. But the SOCOM has bullets with (much) better BC available so it should out perform the Beowulf at distance.
So as you can see, the difference is really not that big. A lot of it depends on personal preferences, or perhaps what your budget is or whether you already reload or similar considerations. You can’t go wrong with either.
NOTE: There now is another prevalent big bore AR on the market, the .450 Bushmaster. Built by Bushmaster with Hornady supplying ammunition, it is a solid design that takes elements from both the SOCOM and Beowulf. As with the Beowulf and SOCOM comparison, this new player may offer things the others don’t and a lot of the decision will be based on factors other than external ballistics.

What is the best twist rate?
One of the reasons .458 was chosen was to allow the use of the commercially available heavy bullets (500 and 600 grains). To stabilize these at subsonic velocities, a relatively fast twist is needed. If you plan on shooting mostly light bullets (250-400) you can get away with slightly slower twist and the slower twist MAY stabilize the 600-grain bullets but likely won’t. Basic guideline is as follows:
Lighter bullets (250-400 grain) – 1 in 18 twist will work, no ill effect if 1 in 14 is used
Heavier bullets (500 and 600 grain) – 1 in 14 twist is needed
(Using the 14 twist with the lighter bullets will NOT reduce accuracy potential.)

What is the optimum barrel length?
The cartridge is intended as a short range “brush buster”. As such, we feel the optimal length is about 16”, as a compromise between handling and velocity. Longer barrels will NOT offer substantially more velocity due to the fact that relatively little powder is available and relatively fast burning powders are used. As a matter of fact, the factory loaded 600-grain subsonic load is designed to achieve complete powder burn in a 9.5” barrel. Most of the uppers that have been built have featured 16” barrels, with the second most popular length being 20”, followed by 10.5” for SBRs/pistols.

What is the shortest possible barrel?
The typical short barrel upper will have a 10.5” barrel; however we have managed to make an AR-15 gas operated upper function with a 6.25” barrel. You can’t go much shorter than that…

What type of velocity can I expect?
Velocity will vary from rifle to rifle and obviously also depend on the bullet that is being loaded. However, some of the typical velocities from a 16” barreled upper are as follows:
300 grain bullet – 1800 to 2000 fps (higher has been recorded)
400 grain bullet – 1600 to 1800 fps
500 grain bullet – 980 to 1300 fps
600 grain bullet – 1000 fps
The Lehigh 86-grain aluminum bullet has been clocked at 3,100 fps...

What type of accuracy can I expect?
As with velocity, accuracy will vary from rifle to rifle. The cartridge, however, is capable of quite respectable accuracy. With hand loads, low power optics and the shooter doing his job, groups as low as 0.5” (yes, true 0.5”) have been recorded. We typically tell folks that 1.0” groups at 100 yards are the norm for the 300-grain JHP load. The 500-grain subsonic load does not appear to be as accurate but it was never meant for ranges beyond maybe 50 yards.

What is the maximum range I can use the .458 SOCOM?
The cartridge was intended for short range work, either in dense brush or otherwise in urban theaters for LEO/MIL applications. As such, after 125-150 yards, the bullets tend to drop off VERY rapidly and we tell folks to consider it a 100-150 yard cartridge. Accomplished shooters can shoot the cartridge accurately at much greater distances, just like the .45-70 was used to decimate the American bison population at 1000 yards. In bolt action rifles with the new Barnes 300-grain TTSX bullet, an LEO has reported 3.1" groups at 300 yards...

What kind of recoil can I expect?
Recoil is subjective, however, most of the folks who have shot it tend to use the comparison to either a 20- or 12-gauge shot gun. The 400-grain loads seem to have the most unpleasant recoil impulse, the 300-grain does not appear that bad nor does the 500- and 600-grain subsonic load. I have shot it in a 10.5” SBR on full auto with 300-gr. JHP loads and found it not that hard to handle. From the bench my .308 has seemed to kick worse. See the next section about some pointers.

What lower, stock, other parts can I use?
The .458 SOCOM was designed to fit any mil-spec lower. Thus, any of the lowers out there that meet mil-spec should readily accept the .458. No modifications should be needed to your lower and no negative effects to the lowers have been reported. Based on customer reports, the following aftermarket modifications can help reduce any felt recoil and make your shooting experience a more enjoyable one:
Stock – the standard A2 stock has a butt plate that becomes a “meat grinder” with the .458 SOCOM. The most popular stock tends to be the ACE Ltd Skeleton stock with the thick rubber recoil pad. Collapsible/telescoping stocks from reputable manufacturers can be used without issue, only one report of a stock failing has been brought to our attention.
Buffer Spring – While the standard spring will work, some shooters prefer a spring with higher spring constant such as the MGI or Wolff
Buffer – Again, the standard buffer will work but the MGI Recoil/Rate Reducing buffer is a popular item among big bore AR shooters
Magazines – the .458 SOCOM was designed to work with any GI/Mil Spec magazine. We have not heard of any particular type or brand of magazine that did not function. Magazine capacities for the different size magazines are as follows:
10 rounds of .223 – 3 rounds of .458 SOCOM
20 rounds of .223 – 7 rounds of .458 SOCOM
30 rounds of .223 – 10 rounds of .458 SOCOM (have heard 12)
40 rounds of .223 – 13 rounds of .458 SOCOM (have heard 15)
The MWG 90-round .223 drum can hold as many as 33-36 rounds of .458 SOCOM which makes for some formidable firepower.
The BETA mag WILL NOT WORK with the SOCOM.
The PMags can be made to work, typically require the removal of the front center rib on the inside of the magazine.

What are the best or preferred optics?
Which is better, Ford, Chevy or Dodge? Because of the recoil, the preferred optic will have longer eye relief than typical. Lower power scopes such as those originally intended for use with a shotgun are popular, however, the vast majority of shooters use either the Aim Point or the EOTech as these seem particularly well suited to the type of shooting done with the .458 SOCOM. A lot of the newer 1-4x type scopes appear well suited as well.

Where can I buy loaded ammo?
Originally, only CorBon offered loaded ammunition, specifically the 300-grain Jacketed Hollow Point, the 400-grain Barnes Round Nose SOLID and the 600-grain Barnes Original SUBSONIC. As of this writing, you can now buy ammo from various ammo outlets and there are several firms producing ammo:
CorBon/Glaser – Dakota Ammo
SBR Ammunition – www.sbr-ammunition.com
Reed’s Ammo – Home Page
Wagner/Accuswage – through Cheaper Than Dirt
Load-X
Other smaller, local firms also offer the SOCOM.

Can I shoot subsonic loads?
Considering this was part of the original design intent, the answer is a resounding YES. Both the 500- and 600-grain subsonic load has proven quite popular and will function without issue through the uppers.

How loud are the subsonic loads?
While not as loud as the 300-gr high velocity load, they are still not quiet enough to forego ear protection.

What about putting a suppressor on one of these?
Several uppers have been fitted with suppressors, either muzzle mounted or semi-integral versions. Different brands have been reported, such as SRT and GemTech, as well as Form 1 versions built by qualified individuals. With the 500- and 600-grain subsonic load they tend to make for a very nice and relatively quiet package. Suppressing a low pressure large bore cartridge has its challenges, and Hollywood has created a false impression of how quiet a suppressed rifle typically will be. These uppers are not like you see in the movies and a lot of the noise is from the action cycling. If you want the ultimate in suppressed .458 SOCOM, the Remington 700 Etronix version with semi-integral suppressor would have to be it. Other calibers are far more suited to suppressing but the SOCOM is no slouch. Remember that the 11.63 x 33 was used in suppressed bolt guns in Vietnam ….

Do I need a muzzle brake? Do you offer one? What about flash hiders?
This depends on how recoil sensitive you are. ANY benefit in terms of recoil will come at the cost of increased noise to the shooter and surroundings. Because of the large bore and relatively low pressure, most muzzle brakes will not be quite as effective with the .458 SOCOM as they might be with a cartridge like the .22-250. We do offer different versions and some folks report that they make a tremendous difference. A lot of it depends on the shooters preference but the more popular version is the Shrewd brand. We also offer a number of different flash hiders, including an A1 birdcage style made by Tromix and a custom-made Smith Enterprises Inc Vortex.

What about reloading?
Because loaded ammo was scarce for a while, the .458 SOCOM with its wide range of bullets available seems to have found a loyal home with the folks that (like to) reload. All the components are available as is load data so reloading is not an issue. Folks have reported as many as 9 reloads on a single case, making it economically attractive for those already set up to do so. With the wide array of .458 bullets available, (re)loading your own ammunition allows you to tailor a load both to your needs and your gun, which means you can work on getting the utmost in terms of accuracy or velocity out of your particular rifle. Some guys really like their pet loads for hunting, while others just like the fact that reloading can drastically reduce the cost of plinking with the SOCOM.

I am new to reloading, would this be a good cartridge to learn on?
To be honest, the SOCOM is relatively new in the world of firearms compared to such rounds as the .30-06, the .45-70 and many others. It would probably not be the best one to learn on, as it has a few idiosyncrasies, but if you like a challenge….

Where do I get brass, bullets, etc.?
The brass is made by Starline and can be bought straight from them or else through the larger reloading specialty outlets like Midway and Graff and Sons. Just about ANY of the .458 diameter bullets out there will work, and these are readily available at most gun stores that offer reloading components. New Starline brass MUST be resized before use.

What is the trim length for the brass?
The official length is 1.575” but you can go as “short” as 1.570”.

How do I resize the brass?
More important than trim length is shoulder set back as this cartridge head spaces on the shoulder. Experienced reloaders will know what this means, but for those that do not – you have to set up your dies such that when you full length size the brass after firing, you do not push the shoulder back down the case. If you were to do so, the case would still chamber, but likely FAIL upon firing. Not a huge issue, just a pain. I have had several do this, before I got my dies dialed in properly. Sometimes the shell holder can make al the difference needed …. I run my dies all the way down to where the fully contact the shell holder and this works for me but again; there are variances in shell holder thickness which can cause problems.

What bullets can I use?
As stated above, just about any .458 diameter bullet, ranging from 86 grains to 600 grains is what we have found out there. Cast lead could be used, but we would recommend limiting the number of cast lead bullets as the lead may foul the gas system. Seating depth can be a bit of a challenge with some of the heavier bullets. NOTE that the crimping groove on many .458 caliber bullets was designed with a totally different cartridge in mind (typically .45-70 or .458 Win Mag). Therefore, the crimping groove will likely NOT line up with the case mouth when seating to an overall length that fits in the magazine (or chambers, there are some bullets that need to be seated deeper due to their profile, such as the 300-grain SinterFire frangible and the 400-grain Speer FN)

What about crimping? Bullet set back?
Crimping is a topic of quite some debate. All the various brands of dies allow you to crimp. Typically crimping is recommended to prevent set back of the bullet due to recoil or during the feeding process. However, several shooters report no issue when not crimping and one accomplished reloader/shooter reported a decline in accuracy when crimping. I tend to put a light crimp on my loaded rounds with my CH dies and have not encountered an issue … yet.

What primers should I use?
The cartridge case uses the large pistol primer pocket and we recommend the CCI350 or the WLP primers. DO NOT use rifle primers as the primer pocket is not deep enough to seat them property which could lead to a very dangerous situation.

What powders should I use?
With a relatively small powder volume and low pressure, the faster rifle powders tend to be the more popular and effective. Typical powders include Hodgdon H110, Winchester Win296, Norma N200, Alliant Reloder7, IMR4198 and VVN110. We have also been hearing that Hodgdon Lil’ Gun is producing great results but my personal experience has been that Reloder7 is just about the most forgiving and versatile for the SOCOM and I feel it probably is the best choice. Your mileage may vary …

Where do I get dies?
The first set of dies was made by CH Tool and Die (CH4D) and they carry them. You can also get dies in .458 SOCOM from Lee, Hornady and Redding.

Which dies are better?
Another Ford versus Chevy debate some would say. There are some differences; I’ll try to highlight the obvious ones.
CH – The CH dies come as a two-die set with no shell holder. I like my CH dies, but customers have reported that the surface finish was rough, leaving the brass appearing scratched. It does not affect the function of the brass but might be less than ideal. The die set does not include a belling die which never bothered me but can make seating flat base bullets more challenging. The seater plug is designed for use with the 300-gr. Spitzer bullet and will not do the tip of the 300-gr. JHP bullets any favors. Having another seater plug such as one for the 44 Magnum can be a plus. The seater dies also serves to put a taper crimp on the case during the top of the stroke.
Lee – the Lee set does have a belling die as well as a separate crimp die. Again, seater plug issues, as the one furnished is too short for the 300-gr. JHP bullets. Using one from a 44 Magnum die set tends to solve this. The die set also comes with the wrong shell holder for some strange reason …. I do not like the decapper set up on the Lee dies but that is a personal preference.
I have not had a chance to test the Hornady dies, but if they are like the .30 Herrett dies I have from them, they should work exceptionally well. We’ve gotten a lot of feedback that the Hornady dies are very good. The Redding dies are exceptionally nice and I like using them perhaps even more than my CH dies...

Can I load these using a Dillon progressive?
You sure can, but it requires a few tricks. You need the shell plate for the .45 ACP and the powder funnel for that one as well. Make sure the dies allow full travel of the ram as that was found to be a problem in one case. The fine folks at Dillon can help you with specifics; I still plod along with my trusty Rock Chucker …

Where can I find load data?
Right now, the best place is to check on the .458 SOCOM Forums under the reloading section at www.458socomforums.com - Index. At least one official manual is supposed to be coming out in 2011 with .458 SOCOM reloading data. Last edited by Lars; 12-30-2010 at 10:58. Reason: combined 2 posts

A very popular cartridge, this 50AE based case contains a .308 style head configuration with O.A.L. of 1.575 necked down to accept a .458 dia. projectile. This case has been chambered in AR-15s and Bolt Guns. Dies are available from Hornady and Lee Precision.

458 SOCOM Live Pilot Finish Reamer
$147.00
PTG removable pilot reamers are produced from premium M-42 tool steel. They are individually hand-stoned to cut smooth and chatter free. Made to SAAMI specifications for standardized cartridges and to the current industry standard for popular wildcat cartridges. They feature removable pilots that are held in place with a screw and a 3/8" square drive shank for use with a tap wrench. Reamers include one bushing of nominal bore diameter (additional bushings sold separately). Right hand cut.

Thanks for that info Biggun, always helpful! So indeed it is a "pistol" round... very cool!

I personally would choose this over any .50 or .499 round for the same reasons it is designed - .458 bullets are ABUNDANT where .50 bullets are rare. That alone makes this a good selling point. Versatility abounds!

I remember there was a feature article a few years ago in Shooting magazine, I even posted a thread about it. Had case dimensions, load recommendations, etc. Need to see if I can dig that up, I can't remember if I have a copy of that mag or not. Would be worth buying a back issue of it!